Question 852: Electrostats & Capacitance

Question

Two electric dipoles of moment $$\mathrm{P}$$ and $$27 \mathrm{P}$$ are placed on a line with their centres $$24 \mathrm{~cm}$$ apart. Their dipole moments are in opposite direction. At which point the electric field will be zero between the dipoles from the centre of dipole of moment P?

Accepted Answer

Dipole of moment p is at a distance x from N
At N,
|E. F. due to dipole 1| = |E. F. due to dipole 2|
$$\begin{aligned}
& 	herefore \quad \frac{1}{4 \pi \varepsilon_0} \cdot \frac{2 \mathrm{p}}{\mathrm{x}^3}=\frac{1}{4 \pi \varepsilon_0} \cdot \frac{2(27 \mathrm{p})}{(24-\mathrm{x})^3} \
& 	herefore \quad \frac{1}{\mathrm{x}^3}=\frac{27}{(24-\mathrm{x})^3} \Rightarrow \mathrm{x}=6 \mathrm{~cm}.
\end{aligned}$$

Answer

6 cm

Answer

8 cm

Answer

10 cm

Answer

12 cm

Electrostats & Capacitance

Two electric dipoles of moment $\mathrm{P} and 27 \mathrm{P} are placed on a line with their centres 24 \mathrm{~cm}$ apart. Their dipole moments are in opposite direction. At which point the electric field will be zero between the dipoles from the centre of dipole of moment P?

Choose the correct answer: